Bleeding between periods

[Bawdrip]

I'm 38. 3 dc. Very regular easy and short periods. But yesterday and today I'm bleeding lightly. My last period was very light and over quicker than usual. I'm day 9 of my cycle. I've never had spotting or bleeding between periods before, no spotting during pregnancy or anything. We had unprotected sex on the last day of my period. I will do a pregnancy test tmrw morning. If it's not that, what ekae coukd it be? I will ring my gp tmrw assuming the test is negative. Should I be worried?

Also does anyone know if covid affects your cycle? I have mild covid symptoms- I seem to be on a second wave of it after 3 weeks of feeling back to normal health. I'm not particularly stresses at the moment so don't think it can be down to stress